Welcome! This tutorial will teach you how to change the brightness of the BBC micro:bit. Let's get started!
### ~
The brightness of the LED screen can be changed by using the `led->set brightness` function. This function takes a number between ``0`` (off) and ``255`` (full brightness).
Let's build a little app that dims the screen when pressing button ``A``.
Add the code `led->plot all` to turn on all the LEDs. Don't hesitate to run your code to see what happens.
```
led.plotAll() // ***
```
The screen starts with a 50% brightness value by default (128). Add a new line of code to set the full brightness (255) using `led->set brightness`.
```
led.setBrightness(255) // ***
led.plotAll()
```
Add a new event handler for `input->on button pressed(A)` and add the code to set the brightness to `64`.
